A review of the existing evidence on the impact of percutaneous coronary intervention (PCI) in the setting of stable coronary artery disease (CAD) indicates that in patients with chronic coronary artery disease and good left ventricular function, PCI does not confer any clear benefit in terms of hard long-term clinical outcomes, such as mortality, myocardial infarction or the need for subsequent revascularization, as compared with medical conservative treatment. By comparing the benefits against cost considerations, it seems that many percutaneous interventions that are currently performed in patients with non-acute CAD are probably not justified. Determination of the functional significance of coronary artery disease can often be a challenge. Conventional coronary angiography and imaging tests, although suitable for risk stratification, may not be satisfactory as independent guides for specific decision-making regarding the optimum management of these patients. The development of more efficient methods for the identification of coronary lesions that should be the target of coronary intervention is certainly needed.